Category Archives: Vitamins & Minerals

‘Tis the season for coughing, sneezing and sniffling. Many of us have stocked our medicine cabinets with vitamins, minerals and herbal remedies to ward off or cure these nasty symptoms of the common cold. Zinc supplements are a particularly frequent treatment, because zinc is known to support immune function. But do zinc supplements actually work?

Zinc is thought to halt the replication of rhinoviruses, the most common cause of colds. A recent scientific analysis pooled data from previous studies that compared oral zinc treatments with placebo or no intervention. It was found that zinc had no significant effect on the severity of symptoms experienced, but zinc did shorten the duration of a cold by an average of 2.63 days in adults. Not all zinc formulations are equally effective, however. Only zinc acetate caused a statistically significant reduction in symptom duration. Zinc gluconate and zinc sulfate were not successful.

So if zinc can help kick a cold faster, how much should we take once we feel the beginnings of a sore throat and runny nose? The evidence says to start using zinc within one to two days after the onset of a cold, but researchers have yet to offer an optimal dose. In the analysis mentioned above, subjects took zinc acetate lozenges every 2-3 hours while awake until symptoms resolved. By my own estimations, this provided about 54-104 mg zinc daily.

Remember that more is not always better. Zinc lozenges may cause a bad taste in your mouth or even nausea. Taking too many, or popping mega-dose zinc tablets can be harmful. The safe upper limit of zinc is set at 40 mg daily. Exceeding this amount for an extended period of time can actually decrease immunity and cause low copper levels.

The bottom line? Zinc may help your body fight the common cold, but if you’re going to load up, do it for a maximum of 7-10 days and be wary of how much zinc you’re ingesting! Read labels and choose supplements or lozenges with zinc acetate (or zincum aceticum) as the main ingredient.

Happy Summer! I’m hoping the warmer weather inspires more of us to dust off our sneakers and get active! But, considering we’re currently enduring an East coast heat wave, we need to take precaution and rehydrate properly when exercising under the mid-day sun.

A typical workout lasting less than 60 minutes usually only requires you to rehydrate with water. However, with more strenuous exercise (indoor or outdoor), it’s necessary to replace both water and electrolytes that are lost through profuse sweating.

Lately, coconut water has been touted as the ultimate post-workout hydration beverage! Coconut water is naturally packed with potassium, which plays a key role in fluid balance and muscle contraction. However, little potassium is actually lost in sweat. During intense physical activity, sodium becomes the more significant mineral to replenish. While pure coconut water straight from the fruit may contain adequate sodium, the amount of sodium in commercial brands of coconut water is not sufficient to replace what’s been excreted.

Electrolyte replacement beverages or “sports drinks” are specifically formulated for athletes. They contain the right proportions of sodium and carbohydrates for proper rehydration and easy digestion. For example, the carbohydrates (i.e. sugar) in Gatorade help the intestine better absorb sodium and fluids, which fights fatigue and prevents dehydration.

My take? Cool off with coconut water while lounging by the pool or after a light workout. When sweating for longer than 1 hour, choose a sports drink that has approximately 120 mg of sodium per 8 ounces. This will help replenish lost sodium and minimize the risk of cramping. In addition, beverages containing about 6 grams of carbs per 8 ounces will be most effective in maximizing water absorption in the gut. That said, many sports drinks are made with about 14-16 grams of carbohydrates per cup. This quantity of carbs is unlikely to cause stomach upset and, with more calories, can offer an extra energy boost during a marathon workout.

Happy St. Patty’s Day!In honor of my Irish ancestors who subsisted on potatoes, I’m celebrating this holiday by highlighting the spud’s nutritional benefits. Potatoes are a humble vegetable, often judged by starch load and preparation method, instead of their rich potassium, fiber and antioxidant content!

The typical American diet is low in fruits and vegetables and, therefore, most of us consume only half the daily potassium recommendation (4,700 mg/day). Potassium is a mineral that plays a role in nerve function, muscle contraction and fluid and electrolyte balance. When combined with an effort to curb your sodium intake, high potassium consumption is associated with the prevention and reversal of high blood pressure. Bananas are a famous source of potassium, yet they contain only 50% of the whopping 844 mg of potassium that a baked Russet potato has to offer.

Put down the peeler! One of the healthiest parts of a potato is the skin, which is packed with fiber and antioxidants. The skin of a medium Russet potato packs 4 grams of fiber (20-35 gm/day is recommended). Fiber can help lower cholesterol, maintain bowel regularity, slow the absorption of carbs into your bloodstream and may decrease the risk of colon and rectal cancer.

Potatoes come in a variety of colors, from red, white and blue, to the orange flesh of a sweet potato. Phytochemicals are plant compounds responsible for these colored pigments. When they act as antioxidants, phytochemicals are thought to be beneficial in protecting against cancer and cardiovascular disease.

Despite their many health benefits, I’m not encouraging you to chow down on scalloped potatoes, French fries, or a baked tater stuffed with all the fixings! Nix the butter, bacon, cheese and sour cream toppings in exchange for steamed broccoli, sautéed onions, fresh herbs and Greek yogurt. I also suggest you try making oven-baked potato wedges. Slice an Idaho potato into 6-8 segments and toss in a bowl with olive oil and rosemary or thyme. Place wedges flat side down on a cookie sheet and bake at 400°F for approximately 20-30 minutes, flipping them at the half-way point. Alternatively, you can use the same technique to prepare bite-sized, oven-roasted, red potatoes (my personal favorite!)

For many of us, the afternoon slump at the office usually triggers a coffee run to the nearest Starbucks. While it’s true that a caffeinated “cup of joe” can perk you up, you may want to rethink how many you’re consuming in one day.

A standard 12-ounce Starbucks coffee may contain as much as 260 milligrams (mg) of caffeine. That’s nearly the amount of caffeine I would recommend you consume in an entire day! I don’t want to pick on coffee though. Tea, soda and energy drinks can also pack a caffeinated punch and there are hidden sources of caffeine, such as chocolate, coffee-flavored ice cream and over the counter cold medicine.

How much is too much? Moderate caffeine consumption – about 300 mg per day for adults – appears relatively safe. Overdoing it on the java, however, can cause temporary undesirable effects, depending on your usual intake and tolerance. Common symptoms may include headaches, trembling, raised heart rate, a spike in blood pressure and increased fluid losses via urine. Consuming caffeine within six hours of bedtime may also interfere with getting a good night’s sleep.

During pregnancy, caffeine crosses the placental barrier, but a baby has only a limited ability to metabolize it. Pregnant women should consult their doctor on how much caffeine is appropriate to consume.

Some studies have indicated that caffeine may be detrimental to bone health, but the research is inconclusive. Ordinary intakes of caffeine (say, the amount in two small cups of coffee), may increase calcium losses in the body, but this may occur only when calcium consumption is low. Studies have also shown that high intakes of coffee, in particular, may inhibit iron and zinc absorption, but it’s not all simply due to caffeine.

Is it best to nix the caffeine all together? Not necessarily. It’s perfectly healthy to indulge in two small cups of coffee per day, as long as you’re not also slugging back sodas and energy drinks. This should provide enough caffeine to give you the energy boost you’re looking for. Plus, there is limited evidence that coffee and tea may actually reduce the risk of developing Parkinson’s disease, dementia and certain types of cancer.

Use the table below to tally how much caffeine you’re consuming and aim for less than 300 mg per day!

A: The Acai berry is a small, round, black-purple fruit that grows on a certain species of palm tree found in Central and South America. You may have seen acai juices, snacks, powders and capsules flood the market in the past few years, as companies increasingly tout the berry as a “superfood,” packed with antioxidants that can protect against aging and cancer. Acai berry products are also said to help people lose weight, fight heart disease and improve arthritis.

In short, evidence to support these health claims is limited. Studies of the antioxidant capacity of acai berries are conflicting. Though supported by a competing company (POM), one study found that pomegranate juice, red wine and blueberry juice have greater antioxidant potency than acai juice (Seeram et al, 2008). In addition, acai products are marketed as dietary supplements, so they escape FDA regulation. The acai berry may not necessarily be harmful, but its presumed power – to enhance sleep and guard against wrinkles, for example – has yet to be verified scientifically. If you’re looking to save a buck, stick to what’s proven to work. Get your daily dose of antioxidants by meeting the recommend 2.5 cups of vegetables and 2 cups of fruit per day.

A: Antioxidants are compounds that offset damage to the body’s cells. Antioxidants, including certain vitamins, minerals and phytochemicals, defend against injuries caused by free radicals. But what’s a free radical? Simply, free radicals are oxygen molecules floating around in your system that contain an unpaired electric charge. This single “electron” looks for a buddy to gain stability and so it destructively steals a second electron from substances like cell membranes and DNA. Free radicals form naturally during the metabolism of food, but are also caused by cigarette smoke, air pollution and UV sun rays. While there are some benefits to free radicals, these highly reactive, unstable molecules are implicated in aging, neurodegenerative diseases and cancer. Fortunately, antioxidants can destroy free radicals, limit their formation and stimulate repair activity at the site of damage.

Antioxidant

Food sources

Recommended Daily Amount

Vitamin C

Orange, grapefruit, mango, strawberries, broccoli

90 mg for men75 mg for women

Vitamin E

Wheat germ oil, sunflower seeds, peanut butter

15 mg

Beta-carotene (Vitamin A precursor)

Carrots, sweet potatoes, broccoli

None established

Selenium

Brazil nuts, tuna, turkey, rice

55 µg

Lycopene

Tomatoes, ketchup, watermelon

None established

Lutein

Dark, leafy greens (e.g. spinach)

None established

Resveratrol

Red grapes

None established

Anthocyanin

Blueberries, raspberries, plums, red grapes

None established

There is no set daily recommendation for most antioxidants; however, eating more fruits and vegetables is the best way to boost your intake. Rely on whole foods, not supplements, since popping high dose capsules can have negative health effects. For example, beta-carotene supplements are associated with higher rates of lung cancer in men; however, smokers are recommended to increase vitamin C intake, due to smoke-induced oxidative damage. My take? Get your antioxidants from food sources, steer clear of mega-dose pills and stick to recommended daily amounts of vitamins & minerals.

Q: My doctor recommended I take a calcium supplement. Which type do you suggest, and when is the best time of day to take it?

A: Calcium supplements come in two forms: calcium citrate or calcium carbonate. Calcium carbonate (e.g. Caltrate®, Viactiv®, Tums®) is cheaper than Calcium citrate (e.g. Citracal®), but research has shown that under normal circumstances, the two forms are equally absorbed and utilized by the body. The exception is in cases of reduced stomach acidity, which occurs often in the elderly or if you take medications that decrease gastric acid secretion. If this is the case, then calcium citrate is the way to go. Check the ingredient list on the back of supplements and multivitamins to know which form of calcium the product contains.

A few rules:

Calcium carbonate products should be taken with meals.

Calcium citrate products can be taken with food or on an empty stomach.

Along with food and antacids, calcium supplements likely inhibit the absorption of medications intended to halt bone loss, such as Fosamax, Actonel or Didronel. After taking one of these drugs, wait at least 30 minutes before ingesting anything except plain water.

Calcium may prevent iron absorption, so if you’re also on supplemental iron, space the two tablets several hours apart.

Healthy adults should aim for 1,000-1,200 mg elemental calcium per day. It’s important to buy a supplement that also contains vitamin D, which helps our body absorb calcium. The recommendation for vitamin D is set at 600 IU daily, but a number of researchers believe this number should even be doubled.

Let’s put things in perspective…One Caltrate®600+D tablet contains 600 mg calcium plus 400 IU of vitamin D. Daily goals can be met with two of these tablets daily. On the other hand, Citracal® Regular 250 mg + D contains 500 mg calcium and 400 IU vitamin D per serving, but a serving is 2 tablets! That means you would need to take 4 Citracal® tablets per day to meet the daily calcium requirement. Viactiv® flavoredchews each have 500 mg calcium and 500 IU vitamin D. Lastly, a single Tums® tablet contains 500 mg of calcium carbonate, but only 200 mg of that is elemental calcium. Bottom line? Be sure to read labels and, of course, inform your doctor of all vitamins, supplements and herbs you’re taking.